fix: apply image slice scale after slice window to avoid mask issues

MSE draws masks on the slice window and expects the sizes to be equivalent. This was presenting problems with the way I was trying to do internal scale as I was applying the scale upfront as the slice window loads and would need to scale the mask to match. Instead, applying the scale only when the output is generated from the slice window.

src/gui/image_slice_window.cpp

@@ -61,12 +61,13 @@ void ImageSlice::centerSelection() {
     }
 }
 
-Image ImageSlice::getSlice() const {
+Image ImageSlice::getSlice(double scale) const {
-  if (selection.width == target_size.GetWidth() && selection.height == target_size.GetHeight() && selection.x == 0 && selection.y == 0) {
+  wxSize scaled_target_size = target_size * scale;
+  if (selection.width == scaled_target_size.GetWidth() && selection.height == scaled_target_size.GetHeight() && selection.x == 0 && selection.y == 0) {
     // exactly the right size
     return source.GetSubImage(selection);
   }
-  Image target(target_size.GetWidth(), target_size.GetHeight(), false);
+  Image target(scaled_target_size.GetWidth(), scaled_target_size.GetHeight(), false);
   if (sharpen && sharpen_amount > 0 && sharpen_amount <= 100) {
     sharp_resample_and_clip(source, target, selection, sharpen_amount);
   } else {
@@ -195,8 +196,8 @@ void ImageSliceWindow::onOk(wxCommandEvent&) {
   EndModal(wxID_OK);
 }
 
-Image ImageSliceWindow::getImage() const {
+Image ImageSliceWindow::getImage(double scale) const {
-  return slice.getSlice();
+  return slice.getSlice(scale);
 }
 
 // ----------------------------------------------------------------------------- : ImageSliceWindow : Controls

src/gui/image_slice_window.hpp

@@ -45,7 +45,7 @@ public:
   /// Attempt to center the current constraints
   void centerSelection();
   /// Get the sliced image
-  Image getSlice() const;
+  Image getSlice(double scale = 1.0) const;
   
   // Zoom factor
   inline double zoomX() const { return target_size.GetWidth()  / (double)selection.width;  }
@@ -63,7 +63,7 @@ public:
   ImageSliceWindow(Window* parent, const Image& source, const wxSize& target_size, const AlphaMask& target_mask);
   
   /// Return the sliced image
-  Image getImage() const;
+  Image getImage(double scale) const;
   
   // --------------------------------------------------- : Data
 private:

src/gui/value/image.cpp

@@ -41,16 +41,17 @@ void ImageValueEditor::sliceImage(const Image& image) {
   AlphaMask mask;
   style().mask.getNoCache(options,mask);
   // slice
-  // Specify a desired size based on the stylesheet and a scale multiplier defined within the user's settings.
+  ImageSliceWindow s(wxGetTopLevelParent(&editor()), image, style().getSize(), mask);
-  // Storing at a greater than 100% resolution allows for better exports >100%, but may change how images look when filters (sharpen) are applied.
-  // Additionally, this bloats the set file size as even under-resolution images are upscaled to the new minimum size.
-  RealSize desired_slice_size = RealSize(style().getSize().width * settings.internal_scale, style().getSize().height * settings.internal_scale);
-  ImageSliceWindow s(wxGetTopLevelParent(&editor()), image, desired_slice_size, mask);
   // clicked ok?
   if (s.ShowModal() == wxID_OK) {
     // store the image into the set
     LocalFileName new_image_file = getLocalPackage().newFileName(field().name, settings.internal_image_extension ? _(".png") : _("")); // a new unique name in the package
-    Image img = s.getImage();
+
+    // Specify a desired size based on the stylesheet and a scale multiplier defined within the user's settings.
+    // Storing at a greater than 100% resolution allows for better exports >100%, but may change how images look when filters (sharpen) are applied.
+    // It also disrupts some of the patterns in use for doing popout planeswalkers since you have to do the math at both scales.
+    // Additionally, this bloats the set file size as even under-resolution images are upscaled to the new minimum size.
+    Image img = s.getImage(settings.internal_scale);
     img.SaveFile(getLocalPackage().nameOut(new_image_file), wxBITMAP_TYPE_PNG); // always use PNG images, see #69. Disk space is cheap anyway.
     addAction(value_action(valueP(), new_image_file));
   }